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Processing
Lunar AVI's Using RegiStax 5

(by Bob Pilz)

Sharpening

After
stacking, we have
an image with greatly reduced noise, but the stacking process also
introduces a
fair amount of softness into the image. A proper sharpening workflow is
necessary to pull out all the detail inherent in the stacked image. The
Wavelets
tab
contains a powerful
sharpening function called Wavelets. I use it as the first step in my
overall
sharpening workflow.

Sharpening
workflow is
a huge subject unto itself, and even controversial, with everyone
seeming to
have their own favorite method. I am no exception. Rather than
duplicate what
I’ve written before, I’ll refer you to an article I wrote for
Selenology Today Journal #9.
It can be found at:http://digilander.libero.it/glrgroup/journal.htm

Example

The
figure below shows the results of
several of the above stages of processing. Due to space limits, this
shows just
a small area North of Hainzel and has been enlarged 1.5x from the
native
recorded size.

The
first section shows the best single
frame from a recording of 15,000 frames. There is some detail, but the
noise is
very evident and prevents any additional sharpening.

The
second section shows the results of
creating an initial reference frame as described earlier for use during
the
Align stage. The visible noise is much reduced as one would expect from
stacking frames (in this case the 10 best frames at each of 9 align
points
spread evenly around the frame), but the detail is starting to smooth
out.
Although the noise is less, it still is not low enough to allow any
significant
degree of sharpening.

The
third section shows the results after
completing optimize and stack stages and shows a stack of 400 frames
(the best
400 at each of 112 align points). A stack of 400 reduces the noise by a
factor
1/20 ( i.e. 1 / SQRT(#frames)). The noise is very low, but the detail
has been
even more smoothed out by the stacking. However, the detail is there
and is
just waiting for sharpening to bring it out. We must have faith J.

The
last section shows the results after
sharpening and contrast/brightening adjustments. All that processing
did its
job and greatly improved on the overall best single frame. The entire
final
can be found here: http://www.pbase.com/bob_p/image/109445362/original
.